In their as received condition, most tungsten carbide powders tend to be irregular in shape, depending on the crystal structure, morphology and the specific method of their production. Plasma processing of tungsten carbide powders has been known to produce spherical particles. In the plasma process, the as-received powder is passed through a high-temperature plasma generated by known ionization techniques using a suitable fluid medium. The high temperatures generated in the plasma cause local or complete melting of the starting tungsten carbide particles, leading to partial or complete spherical shapes. However, the resulting spherical particles may have different compositions compared to the starting tungsten carbide composition. For example, WC is known to lose C and convert to a mixture of WC and W2C as a result of plasma treatment in a neutral gas such as Ar or He. Such decarburization can have deleterious effects both in the properties of the resultant WC powder and when the WC powder is combined with Co to make a WC—Co composite material. For example, W2C may be softer than WC, and the resulting carbon deficient WC—Co compositions may be more brittle. Current processes for plasma treating WC powder are therefore disadvantageous because they produce carbon-deficient WC.